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41.
Renal vein thrombosis can occur as a complication of nephrotic syndrome. We present the case of a young man with nephrotic syndrome caused by minimal change disease who developed acute inferior vena cava and left renal vein thrombosis. He was treated initially with intravenous heparin. Because of the persistence of severe left flank pain and gross hematuria, local infusion of recombinant tissue plasminogen activator was tried, with resolution of thrombi and subsidence of symptoms. Functional preservation of the involved kidney is good, as indicated by Tc-99m DMSA scan (involved kidney, 47.4%; uninvolved kidney, 52.6%). Anticoagulation is usually recommended as the treatment of choice in renal vein thrombosis. We believe that in cases with critical presentations, such as bilateral involvement, extension into inferior vena cava, acute renal failure, pulmonary embolism or severe flank pain, thrombolytic therapy should be considered as a second-line treatment if good response is not obtained with heparin. 相似文献
42.
Inhibition of apoptosis by hyperbaric oxygen in a rat focal cerebral ischemic model. 总被引:45,自引:0,他引:45
Dali Yin Changman Zhou Ikuyo Kusaka John W Calvert Andrew D Parent Anil Nanda John H Zhang 《Journal of cerebral blood flow and metabolism》2003,23(7):855-864
The hypothesis was tested that hyperbaric oxygen therapy (HBO) reduced brain infarction by preventing apoptotic death in ischemic cortex in a rat model of focal cerebral ischemia. Male Sprague-Dawley rats were subjected to middle cerebral artery occlusion/reperfusion (MCAO/R) and subsequently were exposed to HBO (2.5 atmospheres absolute) for 2 h, at 6 h after reperfusion. Rats were killed and brain samples were collected at 24, 48, 72 h, and 7 days after reperfusion. Neurologic deficits, infarction area, and apoptotic changes were evaluated by clinical scores, 2,3,7-triphenyltetrazolium chloride staining, caspase-3 expression, DNA fragmentation assay, and terminal deoxynucleotidyl transferase-mediated 2'-deoxyuridine 5'-triphosphate-biotin nick end labeling (TUNEL)-hematoxylin and eosin (H&E) costaining. In MCAO/R without HBO treatment animals, DNA fragmentation was observed in injured cortex at 24, 48, and 72 h but not in samples at 7 days after reperfusion. Double labeling of brain slides with NeuN and caspase-3 demonstrated neurons in the injured cortex labeled with caspase-3. TUNEL+H&E costaining revealed morphologic apoptotic changes at 24, 48, and 72 h after reperfusion. Hyperbaric oxygen therapy abolished DNA fragmentation and reduced the number of TUNEL-positive cells. Hyperbaric oxygen therapy reduced infarct area and improved neurologic scores at 7 days after reperfusion. One of the molecular mechanisms of HBO-induced brain protection is to prevent apoptosis, and this effect of HBO might preserve more brain tissues and promote neurologic functional recovery. 相似文献
43.
Peripheral blood samples from 57 children with newly diagnosed E- rosette-negative, surface-immunoglobulin negative acute lymphocytic leukemia (ALL) were studied for the presence of a leukemia-associated antigen (ALLA). Ficoll-Hypaque separated cells were tested using a rabbit antiserum to human null lymphoblasts and an indirect immunofluorescent assay. The percentage of ALLA-positive cells were compared to the percentage of lymphoblasts determined by differential counts of a Wright-Giemsa-stained smear of a concurrently obtained peripheral blood sample. The mean ratio of percentage of lymphoblasts to percentage of ALLA-positive cells was 0.90. However, in 13 patients, the ratio of percent of ALLA-positive cells to percent of lymphoblasts was equal to or greater than 2:1. In the blood of 6 additional children (5 newly diagnosed, 1 relapsed patient) in whom no morphologically identifiable lymphoblasts were detected. ALLA-positive cells were present (7%-49%). These results indicate that testing for ALLA-positive cells in a sensitive technique for detection of leukemic cells in children with ALLA-positive ALL. 相似文献
44.
Study Objectives:
To explore whether employment in industries likely to have non-standard work schedules (e.g., manufacturing and service) and occupations with long work-weeks (e.g., managerial/ professional, sales, and transportation) is associated with an increased risk of short sleep duration.Design:
Cross-sectional epidemiologic survey.Setting:
Household-based face-to-face survey of civilian, non-institutionalized US residents.Participants:
Sample adults interviewed for the National Health Interview Survey in 1985 or 1990 (N = 74,734) or between 2004 and 2007 (N = 110,422). Most analyses focused on civilian employed workers interviewed between 2004 and 2007 (N = 66,099).Interventions:
N/AMeasurements and Results:
The weighted prevalence of self-reported short sleep duration, defined as ≤6 h per day, among civilian employed workers from 2004-2007 was 29.9%. Among industry categories, the prevalence of short sleep duration was greatest for management of companies and enterprises (40.5%), followed by transportation/warehousing (37.1%) and manufacturing (34.8%). Occupational categories with the highest prevalence included production occupations in the transportation/warehousing industry, and installation, maintenance, and repair occupations in both the transportation/warehousing industry and the manufacturing industry. In the combined sample from 1985 and 1990, 24.2% of workers reported short sleep duration; the prevalence of short sleep duration was significantly lower during this earlier time period compared to 2004–2007 for 7 of 8 industrial sectors.Conclusions:
Self-reported short sleep duration among US workers varies by industry and occupation, and has increased over the past two decades. These findings suggest the need for further exploration of the relationship between work and sleep, and development of targeted interventions for specific industry/occupation groups.Citation:
Luckhaupt SE; Tak S; Calvert GM. The prevalence of short sleep duration by industry and occupation in the National Health Interview Survey. SLEEP 2010;33(2):149-159 相似文献45.
Julie L Creelan Viola M Calvert David A Graham Samuel J McCullough 《Avian pathology》2006,35(2):173-179
A real-time polymerase chain reaction (PCR) assay was developed to specifically amplify infectious laryngotracheitis virus (ILTV) DNA from field samples. The 222-base-pair PCR fragment was amplified using primers located in a conserved region of the infected cell protein 4 gene that was demonstrated in this work to encompass a single nucleotide polymorphism. Subsequent restriction fragment length polymorphism (RFLP) analysis of real-time PCR amplified fragments from a range of ILTV isolates using the restriction endonuclease MspI enabled differentiation between older ILTV isolates that were prevalent in the 1960s prior to the availability of vaccine strains and more recent isolates that predominantly are identical to vaccine strains. The assay, using real-time PCR, RFLP and sequence analysis, was used to characterize two recent field cases of infectious laryngotracheitis from Northern Ireland. One of the field cases was demonstrated to be similar to older "wild-type" isolates, while the other field case was identified to have a concurrent ILTV infection of both "wild-type" and vaccinal type origin. The assay described here using real-time PCR and RFLP provides a rapid, specific method that enables detection and characterization of ILTV directly from field cases. 相似文献
46.
47.
Broughton S Thomas MR Marston L Calvert SA Marlow N Peacock JL Rafferty GF Greenough A 《Archives of disease in childhood》2007,92(9):776-780
Objectives
To determine whether abnormalities of lung volume and/or airway function were associated with wheeze at follow‐up in infants born very prematurely and to identify risk factors for wheeze.Design
Lung function data obtained at 1 year of age were collated from two cohorts of infants recruited into the UKOS and an RSV study, respectively.Setting
Infant pulmonary function laboratory.Patients
111 infants (mean gestational age 26.3 (SD 1.6) weeks).Interventions
Lung function measurements at 1 year of age corrected for gestational age at birth. Diary cards and respiratory questionnaires were completed to document wheeze.Main outcome measures
Functional residual capacity (FRCpleth and FRCHe), airways resistance (Raw), FRCHe:FRCpleth and tidal breathing parameters (TPTEF:TE).Results
The 60 infants who wheezed at follow‐up had significantly lower mean FRCHe, FRCHe:FRCpleth and TPTEF:TE, but higher mean Raw than the 51 without wheeze. Regression analysis demonstrated that gestational age, length at assessment, family history of atopy and a low FRCHe:FRCpleth were significantly associated with wheeze.Conclusions
Wheeze at follow‐up in very prematurely born infants is associated with gas trapping, suggesting abnormalities of the small airways. 相似文献48.
To investigate the population genetic structure of Trypanosoma evansi from domesticated animals, we have analysed 112 stocks from camels, buffaloes, cattle and horses using the tandemly repeated
coding sequence (MORF2) and minisatellite markers 292 and cysteine-rich acidic integral membrane protein (CRAM). We recorded
a total of six alleles at the MORF2 locus, seven at 292 and 12 at the CRAM loci. Nei’s genetic distance showed reduced allelic
diversity between buffaloes and cattle stocks (1.2) as compared to the diversity between camels and buffaloes (3.75) and camels
and cattle stock (1.69). The mean index of association (I
A
= 0.92) significantly deviated from zero, and the average number of multilocus genotypes (G/N ratio) was 0.21. Twenty-four
multilocus genotypes were defined from the combination of alleles at the three loci. The Kenyan sub-populations showed F
st
= 0.28 and analysis of molecular variance showed significant divergence (22.7%) between the Laikipia, Kulal and Galana regions.
The regional and host distribution of multi-locus genotypes significant population differentiation and high Nei’s genetic
distances suggest existence of genetic sub-structuring within T. evansi stocks while the few multi-locus genotypes and deviation of association index from zero indicate the lack of recombination.
In conclusion, this study reveals that some genetic sub-structuring does occur within T. evansi, which has a clonal population structure. 相似文献
49.
I. R. Peters E. L. Calvert E. J. Hall M. J. Day 《Clinical and Vaccine Immunology : CVI》2004,11(5):841-848
Selective immunoglobulin A (IgA) deficiency is the most common primary immunodeficiency in humans and may be associated with chronic gastrointestinal disease. This observation has led to the suggestion that the high susceptibility of German shepherd dogs (GSD) to chronic enteropathies is related to a deficiency in mucosal IgA production. Relative deficiencies of IgA has been reported in the serum, saliva, tears, and feces of GSD both with and without alimentary disease; however, the findings of different studies are not consistent. The aim of this study was to confirm whether a relative deficiency of IgA exists in the feces of GSD. Feces were collected from healthy GSD (n = 209), Labrador retrievers (n = 96), beagles (n = 19), and miniature schnauzers (n = 32). Fecal IgA, IgM, and IgG were measured by capture enzyme-linked immunosorbent assays. Fecal IgG concentrations in the four breed groups were not significantly different. IgA concentrations were significantly greater in miniature schnauzers than in GSD (P = 0.0003) and Labradors (P = 0.0004) but not significantly different from those in beagles. IgM concentrations were significantly greater in miniature schnauzers than in GSD (P < 0.0001), Labradors (P < 0.0001), and beagles (P = 0.0098). These findings do not support the hypothesis that GSD have a relative deficiency in fecal IgA. The differences in immunoglobulin concentrations measured from a single defecation, between individuals of the same breed and between breeds, as well as the lack of an internal control molecule, make the determination of a normal reference range for all dogs impossible. Therefore, the usefulness of fecal immunoglobulin quantification for the assessment of intestinal immunoglobulin secretion in dogs is limited. 相似文献
50.